Embodiments of the present disclosure generally relate to systems and methods for establishing a communication link with implantable devices, and more particularly capturing and communicating data of interest between an implantable medical device and an external device.
An implantable medical device (“IMD”) is a medical device that is configured to be implanted within a patient anatomy and commonly employ one or more leads with electrodes that either receive or deliver voltage, current or other electromagnetic pulses (generally “energy”) from or to an organ or tissue for diagnostic or therapeutic purposes. In general, IMDs include a battery and electronic circuitry. The electronic circuitry, such as a pulse generator, and/or a microprocessor, is configured to handle RF communication with an external device. Additionally or alternatively, the electronic circuitry is configured to control patient therapy.
IMDs are programmed by, and transmit data to, external devices controlled by physicians and/or the patient. The external devices communicate through wireless communication links with the IMDs. Recently, it has been proposed that IMDs communicate with the external devices using commercial protocols, such as the Bluetooth Low Energy (BLE) protocol and other protocols which are compatible with commercial wireless devices such as tablet computers, smartphones, and the like. By enabling a commercial wireless device to communicate with the IMD using a commercial protocol, the physician and/or patient may easily and/or frequently activate communication between the IMD and the external device.
Certain conventional systems afford the patient the ability to self-activate recording of EGM data. For example, when a patient feels a symptom, the patient is able to activate communication between the external device and the IMD by means of the external device. The external device communicates to the IMD to record and store EGM data corresponding to the time at which the patient experienced a symptom. At a later time, the stored EGM data may be transmitted to a server where the EGM data is accessible to the physician. The physician may access and analyze the uploaded EGM data in order to understand the state of health of the patient.
However, the process of establishing a communication link between the IMD and the external device can be delayed. The IMD may emit advertising pulses using a wireless protocol that can be heard by other wireless devices. The advertising pulses contain information that allows a communication channel to be established between the IMD and the external devise. The advertising pulses may be emitted from the IMD on a periodic basis. In order to conserve the battery life of the IMD and to ensure a small device, the IMD advertising pulses occur at a slow rate to establish the communication channel between the IMD and the external device. The slow rate of the advertising pulses means that it could take an excessive amount of time for the IMD to establish the communication link with the external device.
After the communication link is established between the IMD and the external device, the external device may instruct the IMD to begin recording and storing transient data. However, over the course of the elapsed delay to establish the communication link, there may be transient data related to the symptom the patient has experienced that may also be of interest but that the IMD may not have recorded. The transient data of interest that occurred during the elapsed time delay establishing the communication link may be missed.
A need exists for improved methods and systems for capturing transient data and account for an elapsed delay that occurs while establishing a communication link between the IMD and the external device.